A year after Sewol’s sinking, progress on making sure it won’t happen again is hard to gauge

ANSAN, South Korea—Flower baskets and framed pictures of many of the 250 students lost in South Korea’s ferry disaster last April still sit on the wooden desks of several empty homerooms at Danwon High School.

All of the students who lost their lives came from the second year at Danwon High, just southwest of Seoul. Only 75 students made it back. On a recent school day, one of the 13 who missed the ferry trip slipped into a...